A new IndyCar season begins on Sunday when 22 cars will hit the road for the Grand Prix of St. Petersburg.
There were no less than nine different race winners across the 16 events last season and this season boasts even more intrigue and historic importance given it will include the 100th running of the Indianapolis 500.
This season, drivers will also return to Road America for the first time since 2007, while Phoenix International Raceway is also back on the schedule having not hosted IndyCar since 2005.
Katherine Legge will also be the first face of the newly formed Grace Autosport, the first all-female team in IndyCar history, who will race in round six.
But for now, all the focus remains on St. Petersburg, where Juan Pablo Montoya will be hoping to seal his second-straight victory and launch another assault on the drivers' championship which was snatched from him in the final race of last season by Scott Dixon.
Below, we summarise some of the key contenders in what promises to be another open season.
Dixon returns as reigning champion having secured the title with a win at Sonoma last season. He tied with Montoya for 556 points over the course of the season but won the title courtesy of his three race wins to the Colombian's two. He returns for Chip Ganassi Racing as he chases his fifth career title and third since since 2013.
Juan Pablo Montoya
The Colombian finished second courtesy of a tie-break last year after starting the season in tremendous form by taking out St. Petersburg. The 40-year old Team Penske driver backed it up by winning his second Indianapolis 500 last season, but was still pipped to the title. The former McLaren driver had his best IndyCar season since arriving in 2000 and will be hoping to better that in 2016.
Power was the 2014 champion and third by some distance last season. He has 22 race wins to his name. He was unlucky last year as he was taken out of two races on consecutive ovals through no fault of his own. His chances of the championship were cruelly ended after colliding with team-mate Montoya at Sonoma.
The former Marussia driver has 35 Formula One starts to his name and, after a partial season in the Indy Lights last year - finishing fifth - he will make his competitive IndyCar debut on Sunday. No-one will be expecting Chilton to have a huge impact, but if he can come to grips with the oval tracks and chase victories on the road tracks he already knows he could be a surprise contender. Chilton joins another former Marussia driver, Alexander Rossi, and Spencer Pigot in making his competitive IndyCar debut.
Back in action after suffering serious injuries during practice for last year's Indianapolis 500 in May. His highest finish in the series is eighth (2012, 2013) and he will be looking to add to his four career race wins. The Canadian started 2015 well before his injuries, winning in Louisiana, and will hope for a similar start this season to keep him in the hunt.